Entertainment Companies in general and how they treat artists

I still can't wrap my head around it. Why do entertainment companies (especially the big 4) keep sabotaging their own artists or groups to artificially pump out some new group while the iron is still hot for the already succesful ones? Even on an financial level this is just a plain bad business decision, intentionally tanking sales for already popular and established groups, making fans angry and for some to boycott or initiate mass boycotts/protests (Eg how 2NE1 was horribly mismanaged that led to their disbandment despite their members CLEARLY still wanting to make music)

Like am I genuinely missing something? Why would they eat into a stable revenue stream like that?